Image-guided minimal-step placement of screw into bone

ABSTRACT

The present disclosure describes a device and methods for safely and accurately placing screws into bones with a powered driving device. By employing multiple layers of fail-safe features and image-guidance systems, the powered driving device provides safe, accurate, and efficient screw placement. That is, the powered driving device may continuously monitor a screw advancement and placement and may automatically shutdown when improper placement is detected. Monitoring placement may be conducted by a microcurrent-monitoring system, by an image-guidance system, or by any other appropriate sensory system. Additionally, upon detecting that screw insertion is complete, the powered driving device may be automatically shutdown. As screw placement is continuously simulated by image-guidance in real time, multiple redundant verification steps are eliminated, providing highly accurate screw placement while decreasing clinician error, device contamination, and surgical time, the decreased surgical time associated with decreased patient-recovery time and associated medical costs.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Ser.No. 61/161,332, filed Mar. 18, 2009, the complete disclosure of which ishereby incorporated by reference in its entirety.

INTRODUCTION

Surgical procedures involving the bones of the spine are among the mostdangerous, lengthy, and costly surgeries presently performed. A primaryreason that these surgeries are so dangerous is due to the proximity ofthe spinal bones to the spinal cord. Thus, even slight miscalculationsand inaccuracies during a spinal procedure may have devastating results,including patient paralysis or death. Consequently, spinal surgeriesinvolve meticulous care and multiple safeguards andprecautions—resulting in extremely time-consuming procedures. Althoughprecision and accuracy are paramount, lengthy procedures are associatedwith additional risks and dangers. In fact, studies have found a directrelationship between surgical time and patient recovery time, i.e.,patient recovery time increases as surgical time increases. In addition,surgical time is directly linked to the likelihood of infection, i.e.,the longer a surgical procedure, the more likely a patient is to sufferfrom a secondary infection. Finally, the length of a surgical procedureis directly linked to the cost of that surgical procedure. Thus,increasing the speed, accuracy, and efficiency of delicate medicalprocedures, such as spinal surgery, may improve patient recovery andprofoundly reduce presently-soaring healthcare costs.

As described above, current spinal procedures, including neurosurgical,orthopedic, etc., involve meticulous care in combination with numerousmanual steps and safeguards. For example, image guidance may be employedto repeatedly verify numerous manual screw insertion steps. That is, aguide hole for a screw may be drilled (without image-guidance) and thenverified, the guide hole may be tapped with an awl (manually) and thenverified, the tapped guide hole may be re-tapped to reposition thetrajectory (manually) and then verified, the screw may be rotated intothe verified tapped guide hole (manually) and then verified, the screwmay be removed (manually) and the screw channel may be again verifiedbefore final insertion.

As may be appreciated, current spinal surgeries are primarily manualwith highly redundant verification steps. This redundancy, whilepotentially increasing precision on the one hand, may increase theopportunity for clinician error, device malfunction, and devicecontamination on the other. In addition, as noted above, becausesurgical time is greatly increased by this multi-step procedure, patientrecovery time, risk of infection, and associated medical costs are alsocorrespondingly increased. Indeed, associated medical costs may becompounded by both increased surgical time and staffing in hospitalfacilities and by increased hospital stays due to the increased patientrecovery time and complications brought on by secondary infections.Further, as the present procedures are dependent on manual rotation forplacement of the screw, inaccurate screw placement in patients withdiseased bone or uncharacteristic anatomical landmarks may also beincreased, along with a high probability of multiple X-rays to confirmaccurate screw placement.

As such, there is a need for a highly accurate and efficient procedurefor inserting a screw into a bone during a spinal-fixation procedure.

Image-Guided Minimal-Step Placement of Screw into Bone

The present disclosure describes devices and methods for placing screwsinto bones. Specifically, the disclosed devices allow for poweredinsertion of screws into bones with an unprecedented degree of accuracy,precision and safety. Indeed, the present methods directly address andmeet any potential concerns regarding use of a powered driving device inclose proximity to delicate areas of the body, e.g., the spinal cord andnerves, while also eliminating many of the limitations and detriments ofcurrent procedures. That is, by employing multiple layers of fail-safefeatures, the powered driving devices arguably exceed present multi-stepprocedures in safety. Further, by integrating the powered drivingdevices with image-guidance systems, precision of screw placement isautomatically provided without repeated verification of a plannedtrajectory associated with manual insertion. Indeed, by eliminating manyof the redundant verification steps, the methods provide a decreasedopportunity for clinician error, decreased opportunity for devicecontamination, and decreased surgical time with associated decreasedpatient-recovery time and decreased associated medical costs. In fact,the present methods are estimated to reduce surgical time by up to half,revolutionizing present spinal-fixation procedures and profoundlyimpacting a myriad of other delicate surgical procedures.

Embodiments disclosed herein provide methods for inserting a screw intobone using a powered driving device. For example, according toembodiments, the powered driving device may be registered in animage-guided field. Further, the methods may comprise identifying atarget position for delivering the screw into the bone, where the targetposition is associated with a target insertion location at a targettrajectory, and receiving an indication from the powered driving devicewhen the powered driving device is positioned over the target insertionlocation and is oriented according to the target trajectory. Thereafter,the methods may include docking the powered driving device over thetarget insertion location and initiating the powered driving device toadvance the screw into the bone. During advancement of the screw intothe bone, a position of the screw may be monitored by the powereddriving device. The screw may then be delivered into the targetposition.

According to additional embodiments, a powered driving device forminimal-step placement of a screw into bone is provided. The powereddriving device may comprise a drive component configured for deliveringtorque to a drive shaft, which is communicatively coupled to the drivecomponent. The drive shaft may be configured to rotate axially whentorque is delivered by the drive component. Further, the powered drivingdevice may comprise a drive chamber that encases the drive component andthe drive shaft and houses a screw. When housed in the drive chamber,the screw may couple to the drive shaft. The powered driving device mayalso comprise a monitoring component for detecting a position of thescrew and an alert component for issuing an alert when the monitoringcomponent detects that the screw has an improper trajectory. Inaddition, the powered driving device may comprise a safety trigger forautomatically shutting down the powered driving device when themonitoring component detects the screw is in an improper position.

According to additional embodiments, a method for automatically shuttingdown a powered driving device while inserting a screw into bone may beprovided. The method may comprise monitoring advancement of the screw inreal time during powered delivery of the screw into the bone andautomatically shutting down the powered driving device upon detectingthat the specialized screw is in an improper position.

These and various other features as well as advantages whichcharacterize the systems and methods described herein will be apparentfrom a reading of the following detailed description and a review of theassociated drawings. Additional features are set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the technology. Thebenefits and features of the technology will be realized and attained bythe structures particularly pointed out in the written description andclaims herein as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the embodiments as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawing figures, which form a part of this application,are illustrative of the described technology and are not meant to limitthe scope of the embodiments as claimed in any manner, which scope shallbe based on the claims appended hereto.

FIG. 1 is an illustration of embodiments of surgical devices and systemsfor performing a surgical procedure.

FIG. 2 is an illustration of a first embodiment of a specialized screwas described herein.

FIG. 3A is an illustration of a magnified embodiment of a specializedscrew having a crown portion as described herein.

FIG. 3B is an illustration of a magnified embodiment of a specializedscrew having an alternative crown portion as described herein.

FIG. 3C is an illustration of a top view of an embodiment of a crownportion having a screw interface.

FIG. 3D is an illustration of a side view of an embodiment of a crownportion having a screw interface.

FIG. 4A is an illustration of a partial cross-sectional view of a firstembodiment of a powered driving device as described herein.

FIG. 4B is an illustration of a magnified, partial cross-sectional viewof an embodiment of a powered driving device tip.

FIG. 5 is an illustration of a second embodiment of a powered drivingdevice as described herein.

FIG. 6 is an illustration of a prospective, partial cross-sectional viewof an embodiment of a powered driving device as described herein.

FIG. 7A is an illustration of a sagittal view of an embodiment of aproperly placed screw in a pedicle as described herein.

FIG. 7B is an illustration of an axial view of an embodiment of aproperly placed screw in a pedicle as described herein.

FIG. 7C is an illustration of an axial view of a first improperly placedscrew in a pedicle as described herein.

FIG. 7D is an illustration of an axial view of a second improperlyplaced screw in a pedicle as described herein.

FIG. 8 is a flow-diagram illustrating an embodiment of a method forplacing a screw into a bone using a powered driving device.

FIG. 9 is a flow-diagram illustrating a first embodiment of a method forautomatically shutting down a powered driving device during screwplacement.

FIG. 10 is a flow-diagram illustrating a second embodiment of a methodfor automatically shutting down a powered driving device during screwplacement.

FIG. 11 is a flow-diagram illustrating a third embodiment of a methodfor automatically shutting down a powered driving device during screwplacement.

DETAILED DESCRIPTION

Before the present methods and powered driving devices for image-guided,minimal-step placement of screws into bone are disclosed and described,it is to be understood that this disclosure is not limited to theparticular structures, process steps, or materials disclosed herein, butis extended to equivalents thereof as would be recognized by thoseordinarily skilled in the relevant arts. It should also be understoodthat terminology employed herein is used for the purpose of describingparticular embodiments only and is not intended to be limiting.

The present disclosure describes devices and methods for placing screwsinto bones with a powered driving device. By employing multiple layersof fail-safe features and image-guidance systems, the powered drivingdevices provide safe, accurate, and efficient screw placement. That is,the powered driving devices may continuously monitor a screw advancementand placement and may automatically and substantially immediatelyshutdown when inaccurate advancement or placement is detected.Monitoring placement may be conducted by an electrical currentmonitoring system (e.g., a micro-current monitoring system), by animage-guidance system, or by any other appropriate system. Additionally,upon detecting that insertion is complete, the powered driving devicemay be automatically and substantially immediately shutdown. As screwplacement is continuously simulated by image-guidance in real time,multiple redundant verification steps are eliminated, providing highlyaccurate screw placement while decreasing clinician error, devicecontamination, and surgical time, the decreased surgical time furtherassociated with decreased patient-recovery time and associated medicalcosts.

Although the techniques introduced above and discussed in detail belowmay be implemented for a variety of medical procedures, the presentdisclosure will discuss the implementation of these techniques for usein a power-driven, image-guided, minimal-step placement of a pediclescrew into a pedicle. The reader will understand that the technologydescribed in the context of placing pedicle screws into pedicles couldbe adapted for use with other precision systems in which power-driven,image-guided placement of implants or screws is implicated, e.g.,plates, screws, and other implants for insertion into cranial bones,bones of the extremities, etc.

FIG. 1 is an illustration of embodiments of surgical devices and systemsfor performing a surgical procedure.

The following general discussion relates to various surgical devices andsystems available to a clinician during a surgical procedure, e.g., aspinal-fixation procedure, in an exemplary operating room (OR).According to embodiments related to the spinal-fixation procedure, apatient 110 may be placed in a prone position over a frame (not shown)or table 120 that allows the patient's abdominal region to hang free,preventing intra-abdominal pressure that may increase intra-operativebleeding.

The OR may further provide an image-guidance system, or image-guidednavigation system, including various displays and monitors, one or morecomputing systems, various X-ray and other imaging devices, etc. Forexample, a surgical image-guidance system may be provided that mapspositions of surgical tools and implants onto images of a patient'sanatomy. Both two- and three-dimensional images, sometimes referred toas “image sets,” may be employed by image-guidance systems, includingpreoperative images (i.e., images generated prior to a surgicalprocedure) and intra-operative images (i.e., image sets generated duringthe surgical procedure). Two-dimensional image sets may commonly includefluoroscopic images and may be generated intra-operatively using a C-armfluoroscope, e.g., C-arm fluoroscope 130. Three-dimensional image sets,generally obtained preoperatively, may include one or more of thefollowing: magnetic resonance imaging (MRI) scans, computer tomography(CT) scans, positron emission tomography (PET) scans, and angiographicdata. Indeed, any two- or three-dimensional imaging now known ordeveloped in the future may be employed in an image-guidance systemwithin the spirit of the present disclosure.

According to an embodiment, for example, volumetric data from thepatient 110 may be collected by the C-arm fluoroscope 130, anintra-operative CT scanning device (not shown), or other suitableimaging device, such that a plurality of images may be obtained whilethe device rotates roughly 190 degrees about the patient 110. Thevolumetric data may then be loaded into the image-guidance system andconverted into a plurality of image sets that may be rendered on imagedisplay 150, for example. As illustrated, image display 150 may providea plurality of image views, e.g., transverse, caudal, sagittal, axial,etc., and may provide a plurality of image types, e.g., two- andthree-dimensional image types.

According to some embodiments, a clinician may develop a preoperativesurgical plan by determining a target position of an implant and, basedon the target position, calculating a target insertion location and atarget trajectory for properly guiding the pedicle screw into the targetposition. The surgeon may also determine an estimated size and/or typeof screw, which may later be verified by intra-operative imagingprocedures.

According to embodiments, an image-guidance field may be established byaffixing a stationary tracker to a spinous process of the patient'sbackbone (see FIGS. 7A and 7B for an illustration of a spinous process).The stationary tracker may comprise a plurality of light-emitting diodes(LEDs) that emit pulses, or bursts, of infrared radiation detectable bya stereo camera apparatus 140. For example, stereo camera apparatus 140may be affixed in any suitable location and focused around an area ofinterest, e.g., above surgical table 120, and may be sensitive toinfrared radiation. According to alternative embodiments, the stationarytracker may comprise a plurality of mirror-like balls that passivelyreflect incident infrared radiation (e.g., emitted by an infraredradiation source) and that are detectable by stereo camera apparatus140. According to other embodiments, a magnetic image-guidance systemmay utilize a field generator for producing a magnetic field and thestationary tracker may comprise a plurality of small coils. According tostill other embodiments, a global positioning system (GPS) may beemployed. Data regarding the location of the stationary tracker withinthree-dimensional space may be collected by the stereo camera apparatus140, electromagnetic detector, or GPS system, and may be fed into theimage-guidance system.

Thereafter, according to embodiments, the image-guidance field may beverified using fiducial markers, i.e., markers used as reference pointsto establish XYZ coordinates within the three-dimensional space of theimage-guidance field. Fiducial markers, generally but not limited tofour, may refer to a random array of anatomical landmarks of knownlocation within a patient's body. An image-guided probe, or othersuitable device, may be used to register the fiducial markers to thedisplayed images. According to embodiments, the location of theimage-guided probe may be represented on the display images, e.g., viaany suitable visual indication or icon. The image-guidance system may beverified by touching the image-guided probe to each of the fiducialmarkers to verify that the visual indication of the image-guided probecorresponds to the anatomical landmark recognizable by the clinician onthe images. Specifically, the location of the image-guided probe maycorrespond to the location of the anatomical landmark to within anacceptable degree of deviance, e.g., 1 millimeter (mm). In the case ofan unacceptable degree of image deviance, a point-to-point registrationmay be used to recollect imaging data. Once accuracy of theimage-guidance field is established, the image-guided probe may betouched to other known anatomical features and landmarks within asurgical site, again confirming accuracy of the image-guidance system.

According to embodiments, one or more surgical tools may also beregistered, or calibrated, to the verified image-guidance system. Forexample, each surgical tool may be fitted with light-emitting diodes orglobal positioning systems and data regarding the position of thesurgical tool may be collected by the stereo camera apparatus 140, a GPSsystem, or otherwise. Registration or calibration may refer to theprocess of mapping a tracked position of an actual element withinthree-dimensional space (e.g., device, implant, anatomical landmark,etc.) to a virtual position of that element on image displays. Thus,calibration enables the image-guidance system to continuously track aposition of the one or more surgical tools, or instruments, within thedisplay images in real-time. That is, with knowledge of the relationshipbetween a position of a surgical tool and the patient's anatomy and therelationship between the patient's anatomy and the images, theimage-guidance system is able to continually superimpose arepresentation of the tool on the displayed images that corresponds tothe relationship between the actual tool and the patient's anatomy.Thus, as the detected position of the surgical tool changes within thethree-dimensional space of the patient's anatomy, its representation oneach image may be simultaneously updated in real time. The projectedposition of the surgical tool may be verified by touching the tool tothe various fiducial markers and/or other known anatomical landmarks andconfirming that the projected position of the surgical tool is within anacceptable degree of deviance, e.g., 1 mm, of the anatomical landmarkreflected on each image.

According to embodiments, the exact dimensions of a powered drivingdevice may be loaded into the image-guidance system. Thus, when a tip oran end of the powered driving device is touched to each fiducial marker,the image-guidance system may map the exact dimensions of the powereddriving device into each image. Additionally, exact dimensions ofspecific implants, e.g., a screw, may be loaded into the image-guidancesystem. Upon selection of a particular implant, e.g., a particular sizedscrew (e.g., ranging from about 3.5 to 10 mm in diameter), the imageguidance system may automatically simulate and project the dimensions ofthe particular sized screw onto each image. Further still, theimage-guidance system may identify a specific orientation of the powereddriving device, such that a calculated trajectory for an implantdelivered by the powered driving device may be determined and simulatedon the images. That is, upon determining the calculated trajectory, andwith knowledge of the exact dimensions of the particular screw, theimage-guidance system may simulate a predicted placement of theparticular screw on the images. By altering the specific orientation ofthe powered driving device relative to the patient, the predictedplacement of the particular screw may be recalculated and displayeduntil the clinician is satisfied with the predicted placement.

According to some embodiments, as discussed above, a surgical plan maybe formulated pre-operatively such that a target position of a screw maybe determined prior to surgery. During the surgery, according toembodiments, the surgeon may adjust an image-guided powered drivingdevice until its calculated or virtual trajectory matches the targettrajectory and a simulated screw placement matches the target position.According to embodiments, such adjustments of the powered driving devicemay also enable the clinician to identify a target insertion location ina selected bone for delivery of the screw into the target position.

The above-described image-guidance system may be provided by anysuitable computing system, e.g., computing system 160, for executingimaging and/or simulation software, or any appropriate and usefulimaging software variation. The computing system 160 may comprise amemory and one or more processors for executing the suitable imagingand/or simulation software. The memory may include computer-readablestorage media for storing the suitable software that is executed by oneor more processors. In an embodiment, the memory may include one or moresolid-state storage devices such as flash memory chips.

In an alternative embodiment, the memory may be mass storage connectedto the one or more processors via a communications bus, for example.Although the description of computer-readable storage media containedherein refers to a solid-state storage, computer-readable storage mediamay be any available media accessible by the one or more processors.Computer-readable storage media may include non-transitory, volatile andnon-volatile, removable and non-removable media implemented in anymethod or technology for storage of information, e.g.,computer-executable instructions, data structures, program modules orother data. Computer-readable storage media includes, but is not limitedto, RAM, ROM, EPROM, EEPROM, flash memory or other solid state memorytechnology, CD-ROM, DVD, or other optical storage, magnetic cassettes,magnetic tape, magnetic disk storage or other magnetic storage devices,or any other medium which can be used to store the desired informationand which can be accessed by the computer.

According to embodiments, computing system 160 may also containcommunications connection(s), e.g., communication media, which allow thecomputing device to communicate with other devices. Communication mediamay embody computer-readable instructions, data structures, programmodules, or other data in a modulated data signal, such as a carrierwave or other transport mechanism, and includes any information deliverymedia. The described communications connections and media are providedby way of example only and any suitable means of communicating betweencomputer systems may be used within the spirit of the presentdisclosure.

Computing system 160 may also include input device(s), such as keyboard165, and/or a mouse, pen, voice input device, touch input device, etc.(not shown). Output device(s), such as display 170, may also beincluded. The computing system 160 may operate in a networkedenvironment using logical connections to one or more remote computing,input/output devices, etc., for example, neuro-monitoring apparatus 180,stereo camera apparatus 140, image display 150, etc. The logicalconnections between the computing system 160 and the remote devices mayinclude a local area network (LAN), a wide area network (WAN), or anyother suitable network. With reference to a LAN networking environment,the computing system 160 may be connected to the LAN through a networkinterface or adapter. With reference to a WAN networking environment,the computing system 160 may include a modem or other means forestablishing communications over the WAN, such as the Internet. Thedescribed network connections are provided by way of example only andany suitable means of establishing a communications link betweencomputer systems may be used.

The OR may also be equipped with neuro-monitoring apparatus 180.Intra-operative neuro-monitoring during a surgical procedure may includerecording somatosensory evoked potentials (SSEP), motor evokedpotentials (MEP), or electromyography (EMG). For example, the recordeddata may be collected to detect indications of potential neurologicalcompromise during the surgery. In general, a clinician may couple pairsof stimulating and recording electrodes via leads 185 to a plurality ofprimary muscle groups and to a computer system, e.g., laptop 190.Software executed by laptop 190 may selectively activate eachstimulating electrode at specific intervals and may process and displaythe electrophysiologic signals as they are detected or registered by acorresponding recording electrode. As such, the clinician may observeand evaluate the electrophysiologic signals in real time during thesurgery.

As may be appreciated, illustration and description of the varioussurgical devices and systems for performing surgical procedures areprovided for purposes of explanation and example only. Indeed, anysurgical devices and systems either now known or developed in the futurefor performing a spinal-fixation procedure may be used in combinationwith the disclosed powered driving device within the spirit of thepresent disclosure.

FIG. 2 is an illustration of a first embodiment of a specialized screwas described herein.

Specialized screw 200 illustrates a first embodiment of a specializedself-drilling, self-tapping screw. A specialized screw may refer to anysuitable screw that may be used in combination with a powered drivingdevice, as described herein, for insertion into bone. Further, suitablescrews may or may not comprise each feature of the described embodiment,e.g., specialized screw 200, including described self-drilling and/orself-tapping features. That is, other suitable screw designs may beinserted into bone via a powered driving device as disclosed herein andmay be included within the scope of the present disclosure.

According to embodiments, specialized screw 200 may be made of anysuitable, non-toxic, material for insertion into a bone. Suitablematerials may include, but are not limited to, titanium and stainlesssteel. Specialized screw 200 may further include a plurality of screwportions. For example, a first screw portion, e.g., tip portion 210, mayimplement a self-drilling function of specialized screw 200. Features oftip portion 210 may include a suitable degree of hardness such thatembodiments of specialized screw 200 may easily penetrate the hard outercortex of bone. Tip portion 210 may also exhibit a suitable degree ofsharpness such that specialized screw 200 is prevented from skipping,rolling off, or walking off the bone in the absence of a pre-drilledguide hole. Tip portion 210 may further include any suitable shape orconfiguration such that specialized screw 200 embodies the disclosedself-drilling function.

According to embodiments, a second screw portion may also be provided,e.g., tapping portion 220. For example, tapping portion 220 may extendfrom within tip portion 210 into a threaded portion of specialized screw200 and may facilitate a self-tapping function of specialized screw 200.Self-tapping enables embodiments of specialized screw 200 to accuratelyand easily advance through the self-drilled hole provided by tip portion210. Further, tapping portion 220 may enable specialized screw 200 tocut and remove bone as it is placed or inserted, preventing specializedscrew 200 from fracturing bone. Embodiments of tapping portion 220 mayinclude a sharp cutting flute 230, running counter to screw threads 240and roughly parallel to a length of specialized screw 200. According toembodiments, sharp cutting flute 230 may implement the self-tappingfunction of specialized screw 200. According to embodiments, the tappingportion 220 may further include any suitable configuration foraccomplishing the disclosed self-tapping function.

As may be appreciated, illustration and description of the variousfeatures and functions associated with specialized screw 200 areprovided for purposes of explanation and example only. Indeed, anycompatible screw for use with a powered driving device for insertioninto bone may be included within the spirit of the present disclosure.

FIG. 3A is an illustration of a magnified embodiment of a specializedscrew having a crown portion as described herein. FIG. 3B is anillustration of a magnified embodiment of a specialized screw having analternative crown portion. FIG. 3C is an illustration of a top view ofan embodiment of a crown portion having a screw interface. FIG. 3D is anillustration of a side view of an embodiment of a crown portion having ascrew interface.

FIG. 3A is an illustration of a magnified embodiment of a specializedscrew having a crown portion as described herein.

Similar to FIG. 2, FIG. 3A also illustrates a specialized self-drilling,self-tapping screw, e.g., specialized screw 300. As noted above, aspecialized screw may refer to any suitable screw that may be used incombination with a powered driving device, as described herein, forinsertion into bone. Further, suitable screws may or may not compriseeach feature of the described embodiment, e.g., specialized screw 300,including described self-drilling and/or self-tapping features. That is,other suitable screw designs may be included within the definition of aspecialized screw and may be inserted into bone via a powered drivingdevice as disclosed herein.

The disclosed specialized screw 300 may also include a plurality ofscrew portions. For example, specialized screw 300 may include a tipportion, a tapping portion, a thread portion, and a crown portion. Thetip portion of specialized screw 300, i.e., tip portion 310, mayimplement a self-drilling function of specialized screw 300. Features oftip portion 310 may include a suitable degree of hardness such thatembodiments of the specialized screw 300 may easily penetrate the hardouter cortex of bone. For example, titanium or similar metal alloy mayprovide such suitable degree of hardness. The tip portion 310 may alsoexhibit a suitable degree of sharpness such that specialized screw 300is prevented from skipping, rolling off, or walking off the bone in theabsence of a pre-drilled guide hole. That is, the tip portion 310 mayautomatically create a guide hole when docked on bone by virtue of thesuitable degree of sharpness. Indeed, according to embodiments, tipportion 310 may include any suitable shape or configuration such thatthe specialized screw 300 embodies the disclosed self-drilling function.

Embodiments of the specialized screw 300 may also include a tappingportion, i.e., tapping portion 320. Tapping portion 320 may refer to aportion of specialized screw 300 comprising a sharp cutting flute 330that runs counter to screw threads and roughly parallel to a length ofthe specialized screw 300. The tapping portion 320 may extend from aregion partially within tip portion 310 through a lower region of threadportion 340. That is, according to some embodiments, tapping portion 320may span a plurality of lower screw threads that extend from tip portion310, e.g., three lower screw threads. Sharp cutting flute 330 mayimplement a self-tapping function of specialized screw 300. Self-tappingenables embodiments of specialized screw 300 to accurately and easilyadvance through the self-drilled hole provided by tip portion 310. Thatis, sharp cutting flute 330 may enable embodiments of specialized screw300 to cut and remove bone during insertion, preventing specializedscrew 300 from fracturing bone. According to embodiments, tappingportion 320 may further include any suitable configuration foraccomplishing the disclosed self-tapping function.

Embodiments of specialized screw 300 may also include thread portion340. Thread portion 340 may include screw threads for engaging the boneand advancing the specialized screw 300. According to embodiments, thescrew threads may comprise a single helical ridge 350 that spirals aboutthread portion 340 from tip portion 310 to just below crown portion 360.According to embodiments, helical ridge 350 may comprise a suitabledegree of sharpness such that specialized screw 300 appropriatelyengages bone for secure placement. Additionally or alternatively, threadportion 340 may further include any suitable configuration foraccomplishing the disclosed secure placement of specialized screw 300into bone.

Embodiments of specialized screw 300 may further include a crown portion360. Crown portion 360 may correspond to a top portion of specializedscrew 300. Some embodiments of a crown portion may include a headlesstype crown (shown) or a fixed-head type crown (not shown).

FIG. 3B is an illustration of a magnified embodiment of a specializedscrew having an alternative crown portion.

According to embodiments, crown portions may include headless type andfixed-head type crowns. For example, crown portion 360 embodies headlesstype crown 365, while alternative crown portion 370 embodies fixed-headtype crown 375. According to embodiments, fixed-head type crown 375 mayinclude an integrated apparatus for attaching a stabilizing rodfollowing pedicle screw placement, for example. Alternatively, headlesstype crowns, e.g., headless type crown 365, may not comprise suchintegrated apparatus for attaching a stabilizing rod. Rather, afterinsertion of a headless type specialized screw, a cap configured forattaching a stabilizing rod may be coupled to headless type crown 365.As should be appreciated, embodiments of the powered driving device maybe adapted for delivering a fixed head, a headless type, or any othercompatible type of specialized screw 300.

FIG. 3C is an illustration of a top view of an embodiment of a crownportion having a screw interface.

According to embodiments, crown portion 360 (shown from top view) andalternative crown portion (not shown) may further include a suitablescrew interface 380 for engaging a drive shaft interface of a powereddriving device, as disclosed herein. As illustrated by the top view,according to embodiments, suitable screw interface 380 may include anycommon drive design, e.g., octagonal design 385 (shown), Robertson(square, not shown), hexed (not shown), Torx (star, not shown), etc., ormay include any other suitable specialized drive design (not shown) forproperly and securely engaging the drive shaft interface (not shown).According to some embodiments, suitable screw interface 380, havingoctagonal design 385 (shown) or other design (not shown), may furthercomprise a conical portion 395 for securely engaging and mating suitablescrew interface 380 to the drive shaft interface (not shown).

FIG. 3D is an illustration of a side view of an embodiment of a crownportion having a screw interface.

As illustrated by the side view according to embodiments, suitable screwinterface 380 may be provided as an aperture 390 (shown as dashedoutline) within crown portion 360 (shown) or alternative crown portion(not shown). According to some embodiments, suitable screw interface380, having octagonal design 385 (shown) or other design (not shown),may further comprise a conical portion 395 for securely engaging andmating suitable screw interface 380 to the drive shaft interface (notshown). As may be appreciated, suitable screw interface 380 may alsoinclude any other suitable portion (not shown) for securely engaging andmating suitable screw interface 380 to the drive shaft interface (notshown).

As may be appreciated, illustration and description of the variousfeatures and functions associated with specialized screw 300 areprovided for purposes of explanation and example only. Indeed, anycompatible screw for use with a powered driving device in a surgicalprocedure may be included within the spirit of the present disclosure.

FIG. 4A is an illustration of a partial cross-sectional view of a firstembodiment of a powered driving device as described herein. FIG. 4B isan illustration of a magnified, partial cross-sectional view of anembodiment of a powered driving device tip.

As illustrated in FIG. 4A, the powered driving device, e.g., powereddriving device 400, may include any suitable powered driving device foraccurately inserting a specialized screw into a bone. Powered drivingdevice 400 may further comprise an elongated, cylindrical drive chamber410. According to embodiments, drive chamber 410 may be configured tohouse a plurality of various specialized screw types and sizes,including various headless and fixed-head type and various length anddiameter screws. That is, drive chamber 410 may be adjustable orotherwise suitable for accommodating various types and sizes ofspecialized screws. According to other embodiments, drive chamber 410may be specifically manufactured for delivery of particular specializedscrew types and size ranges, for example. According to this embodiment,a plurality of different sized powered driving devices may bemanufactured corresponding to the particular specialized screw types andsize ranges. According to embodiments, specialized screws may be loadedinto drive chamber 410 and coupled to a drive shaft 425 via any suitablemeans.

According to embodiments, a position of the specialized screw 415 may bemonitored by various systems and/or devices associated with the powereddriving device 400. For example, a microcurrent-monitoring system, animage-guidance system, a bone-density monitoring system, apressure-sensitive system, or any other suitable monitoring system maydetect when specialized screw 415 is in an improper position near orcontacting cortical bone and/or is oriented according to an impropertrajectory.

According to embodiments, drive chamber 410 may be further configured,as discussed above, to deliver or pass an electric current, e.g., amicrocurrent, to a specialized screw housed in drive chamber 410, e.g.,specialized screw 415. For example, the microcurrent may be deliveredvia any suitable electric generator for providing voltage and may bepassed by conductors 430 to drive shaft 425. According to someembodiments, the suitable electric generator may be provided atneuro-monitoring apparatus 180 and microcurrent may be passed to thepowered driving device 400 via lead apparatus 440, for example.According to other embodiments, the suitable electric generator may beconfigured within the powered driving device 400.

According to alternative embodiments, delivering the microcurrent may beinitiated via any suitable button, switch, etc. (not shown). Forexample, upon partial insertion of the specialized screw 415 into thebone, delivery of the microcurrent may be initiated. Partial insertionmay correspond to a particular number of revolutions of the specializedscrew 415 by the powered driving device, a particular depth of thespecialized screw 415 as calculated by the image-guidance system, or anyother predetermined threshold. According to some embodiments,microcurrent may be automatically initiated by the powered drivingdevice upon detecting the predetermined threshold has been met.According to alternative embodiments, the microcurrent may be initiatedwhen the powered driving device is appropriately docked onto the bone.According to other embodiments, the microcurrent may be initiatedmanually at the discretion of the clinician.

As described above, the microcurrent may be initiated by any suitableelectric generator for providing voltage and may be passed by conductors430 to drive shaft 425. According to embodiments, drive shaft 425 maycomprise conductive properties and may thereby pass the microcurrent tospecialized screw 415. According to embodiments, conductors 430 may takeany suitable form such that a suitable electric connection may beprovided between conductors 430 and drive shaft 425. Conductors 430 maybe comprised of any type of conductive metal, metal alloy, or othersuitable conductive material. For example conductors 430 may includemetallic nodes (shown), wire brushes (not shown), etc.

According to alternative embodiments, drive chamber 410 may be made of asuitable non-conductive material and another component or apparatus (notshown) may be coupled to drive component 420, or otherwise, and may beconfigured to deliver microcurrent to specialized screw 415 via driveshaft 425, or otherwise.

According to further embodiments, lead apparatus 440 may be coupled to aneuro-monitoring apparatus, e.g., neuro-monitoring apparatus 180, formonitoring a microcurrent across the bone. For example, lead apparatus440 may include an appropriate adapter and may be inserted into anappropriate receptacle of powered driving device 400, e.g., on handleportion 475. According to other embodiments, neuro-monitoring apparatus180 may be coupled to powered driving device 400 via any suitable means.According to embodiments, a grounding lead may be attached at one end toa suitable location on the patient's body, e.g., the patient's abdominalarea, and attached at another end to the neuro-monitoring apparatus 180.According to embodiments, the grounding lead may comprise a small-gaugeneedle or patch for affixing to the patient.

According to embodiments, upon partial insertion of the specializedscrew 415 into the bone, e.g., a vertebral bone, a microcurrentdelivered to specialized screw 415 may flow through or across the bone.As may be appreciated, composition of the vertebral bone may not beuniform and may include, inter alia, a less-resistive trabecular layerand a more-resistive cortical layer (see FIGS. 7B-7D for furtherillustration of bone layers). According to embodiments, the microcurrentmay be represented according to the following electrical equation (Ohm'sLaw):I=E/RThat is, where voltage (E) is constant, microcurrent (I) will decreaseas resistance (R) increases. According to embodiments, microcurrentdetected across the bone may change based on the resistance and/ordensity of the bone surrounding the specialized screw. For example, whenthe specialized screw is positioned within the internal trabecularlayer, the microcurrent may register at about 20 mA. In the alternative,when the specialized screw is positioned near or within the densecortical layer, i.e., in danger of traversing or fracturing the bone,the microcurrent may register at about 12 mA or less. According tofurther embodiments, if in fact the specialized screw traverses thebone, contacting tissue and/or nerves, microcurrent may register at 2mA. That is, as the resistance of tissues and/or nerves may beconsiderably less that that of either the trabecular bone layer or thecortical bone layer, the microcurrent may easily pass through the nervetissue. Thus, delivered microcurrent as low as 2 mA may register acrossnerve tissue. However, according to embodiments disclosed herein,shutdown of the powered driving device may preferably occur when thedevice comes in contact with the cortical bone, before it ever traversesand/or fractures the bone.

According to embodiments, the microcurrent may be monitored by variousmicrocurrent monitoring systems, including monitoring apparatus withinthe powered driving device 400, the neuro-monitoring apparatus 180, orany other suitable microcurrent-monitoring system. According toalternative embodiments, resistance and/or voltage may be monitored anda microcurrent may be derived by any appropriate system according toOhm's Law, as described above. As may be appreciated, according to someembodiments, the powered driving device 400 may include an internalammeter (not shown), multimeter (not shown), or any other suitabledevice for measuring a microcurrent across a bone. Alternatively,neuro-monitoring apparatus 180 may monitor the microcurrent across thebone based on data passed via lead apparatus 440 and/or the groundinglead. Similarly, any other suitable microcurrent-monitoring system maybe provided.

As will be discussed further herein, the powered driving device 400 maybe automatically and substantially immediately shutdown whenmicrocurrent across the bone registers below a predetermined threshold,e.g., at or below about 12 mA, indicative that specialized screw 415 mayimminently traverse and/or fracture the bone. According to embodiments,breach of the predetermined threshold may be detected byneuro-monitoring apparatus 180, the internal ammeter, or other device,and may be communicated near instantaneously to a safety triggercomponent (not shown) for automatically shutting off powered drivingdevice 400. Stated differently, fluctuations in microcurrent readingsmay be monitored and evaluated such that fluctuations below apredetermined threshold may initiate near-instantaneous automaticshutdown of the powered driving device 400.

Additionally or alternatively, continuous monitoring of the microcurrentwhile the specialized screw 415 is being advanced into the bone may beperformed by neuro-monitoring apparatus 180 and/or the internal ammeter,for example. According to embodiments, during specialized screwplacement, when the microcurrent is recorded within a predeterminedrange, e.g., a range between about 12 and 16 mA for example, an alertmay be generated by an alert module 490 such that a clinician may bewarned that specialized screw 415 may be approaching the cortical layerand/or that specialized screw 415 may have an improper trajectory. Alertmodule 490 may issue an alert via any suitable method, e.g., a visualalert and/or an audio alert, etc.

According to alternative embodiments, other suitable sensors or devicesmay be employed to monitor the position of a specialized screw (notshown). For example, other suitable devices may be employed to detect abone density around the specialized screw. As a bone density of thecortical layer may be greater than a bone density of the trabecularlayer, bone density may be used to indicate that a specialized screw isnearing the cortical layer and is in danger of traversing the bone (seeFIGS. 7A and 7B for further illustration of bone layers). Alternatively,other suitable sensors may be employed to detect a proximity to thecortical bone layer via any other suitable means. For example, sonicdevices, radar devices, pressure-sensitive devices, heat-sensitivedevices, etc., may be employed to detect bone density and/or a proximityto the cortical bone layer. According to embodiments, upon anydetermination that the specialized screw may traverse the bone, thesafety trigger component may automatically shutdown the powered drivingdevice 400.

According to embodiments, drive shaft 425 may be mechanically orotherwise coupled to a drive component 420. Drive component 420 mayprovide a suitable force in the form of torque, or otherwise, via driveshaft 425 to a specialized screw housed in drive chamber 410. Accordingto some embodiments, drive component 420 may provide controlled torqueand/or rotations per minute (rpm) such that the specialized screw maynot be rotated above a consistent, controlled predetermined rate. Driveshaft 425 may further include a drive shaft interface (not shown) forengaging a screw interface on the crown portion of specialized screw415. Suitable force may be delivered by a pneumatic apparatus, hydraulicapparatus, spring apparatus, gear apparatus, or any other suitableforce-delivery mechanism.

According to embodiments, the drive component 420 may be mechanically,electrically, or otherwise coupled to a suitable power source by powercoupling apparatus 435. According to embodiments, power couplingapparatus 435 may comprise an electrical cord or a pressurized air hose,for example. According to alternative embodiments, power couplingapparatus 435 may be replaced by a battery pack or other suitablecordless power-delivery apparatus. According to alternative embodiments,power coupling apparatus 435 and lead apparatus 440 may be encased in asingle insulated cord apparatus (not shown).

According to embodiments, the suitable power source may provideelectrical (via an electrical cord or a battery pack), pneumatic (via apressurized air hose), or other suitable power to the drive component420 for delivering suitable force for insertion of the specialized screw415 into bone. The suitable power source may be initiated by a powerswitch 445, by a pneumatic pedal or other suitable pneumatic initiationdevice (not shown), or by any other suitable power-initiation device.According to embodiments, the power switch 445 may be further configuredto prevent accidental power-on or power-off. According to embodiments,the safety trigger component may be coupled to the power switch 445 tofacilitate automatic shutdown of powered driving device 400. Accordingto alternative embodiments, the safety trigger component may comprise analternative power-off switch. In the case of electrical embodiments ofthe powered driving device, the electrical current utilized for poweringthe driving device may be adequately insulated from an internal ammeterand/or grounded apart from neuro-monitoring apparatus 180 such thatmicrocurrent across the bone may be independently monitored anddetected.

Powered driving device 400 may also be configured to include a trackingapparatus 450 (partially shown) enabling the image-guidance system todetermine a location the of the powered driving device 400 and anorientation of the powered driving device 400 in real time. Trackingapparatus 450 may communicate an actual location of powered drivingdevice 400 within the three-dimensional space of the image-guidancefield to a computer system, e.g., computing system 160, by wired orwireless communication, as described above. That is, based on theorientation of the powered driving device 400 communicated by trackingapparatus 450, a predicted trajectory of the specialized screw 415 maybe calculated and a simulated placement may be provided on imagedisplays in real-time. That is, according to embodiments, when a powereddriving device tip 455 is placed on or near a patient's skin, based onthe exact dimensions of specialized screw 415, a simulated placement ofthe specialized screw may be calculated and displayed in real time,enabling a clinician to determine an appropriate incision location.Additionally or alternatively, during insertion of the specializedscrew, a simulated placement of the specialized screw may becontinuously re-calculated and displayed in real time, enabling aclinician to continually verify accurate placement of the specializedscrew.

According to embodiments, as described above, powered driving device 400may further include alert module 490. According to embodiments, alertmodule 490 may issue alerts regarding initial positioning while powereddriving device 400 is being adjusted over a surgical site. That is,alert module 490 may indicate by a visual alert and/or an audio alertwhen powered driving device 400 is positioned in an appropriate dockinglocation and oriented with a proper trajectory. For example, the alertmodule may issue a first alert, e.g., a yellow light, indicating thatthe powered driving device 400 is not positioned over a target insertionlocation and/or is not oriented according to a target trajectory.However, as the powered driving device 400 is adjusted about thesurgical site, alert module 490 may issue a second alert, e.g., a greenlight, indicating that the powered driving device 400 is positioned overthe target insertion location and is oriented according to the targettrajectory. Thereafter, upon receiving an indication from alert module490 that the powered driving device 400 is properly positioned, thepowered driving device 400 may be docked onto the bone in the properposition.

According to other embodiments, the alert module 490 may provide variousalerts regarding proper positioning of the specialized screw 415 whileit is being delivered. According to embodiments, the alert module 490may be provided in any suitable location on powered driving device 400so as to communicate the various alerts to a clinician. For example, thealert module 490 may issue alerts when minor misalignments of thespecialized screw are detected, e.g., an improper trajectory. Forexample, according to embodiments, the alert module 490 may receivemicrocurrent-monitoring data from the neuro-monitoring apparatus 180and/or the internal ammeter indicating an improper position ofspecialized screw 415 within bone. As described above, an alert may begenerated when a microcurrent is detected within a predetermined range,e.g., about 12-16 mA. Additionally or alternatively, the alert modulemay receive data regarding a virtual trajectory of the specialized screw415 from the image-guidance system. For example, when the image-guidancesystem predicts that specialized screw 415 is advancing according to animproper trajectory that may not deliver specialized screw 415 into thetarget position, the alert module 490 may issue a warning to theclinician. As described above, according to embodiments, the alertmodule 490 may alert the clinician by any suitable method, for instanceby an audible alert or by a visual alert on the image display and/ordisposed on the powered driving device 400 itself. According toembodiments, alert module 490 may be communicatively coupled to thesafety trigger component (not shown) and, when alert module 490 detectsthat the specialized screw 415 may imminently traverse and/or fracturethe bone, the alert module 490 may substantially immediately command thesafety trigger component to initiate shutdown of the powered drivingdevice 400. According to alternative embodiments, alert module 490 andthe safety trigger component may be comprised in a single component.

According to further embodiments, the alert module 490 may issue analert when it detects malfunctions in the hardware and/or software ofthe image-guidance system, e.g., inconsistencies in a predicted orsimulated placement and/or predicted or virtual trajectory of powereddriving device 400.

Powered driving device 400 may also include a handle portion 475 thatprovides the clinician with an ergonomically adapted handle for stable,comfortable and effective use of the powered driving device 400 duringan implantation procedure. According to embodiments, the handle may beconfigured in any appropriate orientation, e.g., angled roughly 35degrees to 55 degrees from the drive chamber, roughly perpendicular tothe drive chamber at about 90 degrees, or roughly linear to the drivechamber at about 180 degrees. The handle portion 475 may be furtheradapted to provide tactile signals to the clinician during placementprocedures in order to provide additional verification feedback foraccurate placement of the specialized screw.

Powered driving device 400 may further include a trigger drive 480. Thetrigger drive 480, or other suitable mechanism, may initiate insertionof the specialized screw 415. Particularly, the trigger drive 480 mayinduce drive component 420 to begin delivering force to the specializedscrew 415. Trigger drive 480 may also be configured to simultaneouslytrigger the virtual image guidance display such that the clinician isprovided with real-time virtual feedback regarding the orientation andadvancement of specialized screw 415. Alternatively, trigger drive 480may include a trigger guidance control 485 that may initiate imageguidance upon demand when desired by the clinician. According toalternative embodiments, trigger guidance control 485 may be provided ina separate location from trigger drive 480. The trigger drive 480 may befurther configured to provide safety components that prevent accidentaltriggering or shut off.

FIG. 4B is an illustration of a magnified, partial cross-sectional viewof an embodiment of a powered driving device tip.

According to embodiments, powered driving device 400 may furthercomprise powered driving device tip 455, as described above. Powereddriving device tip 455 may comprise docking teeth 460 and stop component465. According to embodiments, docking teeth 460 may be configured toprovide stabilization support for docking powered driving device 400 onan anatomical landmark or process. Specifically, powered driving device400 may be docked on the bone in an appropriate insertion location forsafely and accurately placing specialized screw 415 into a bone.According to embodiments, a tip portion of specialized screw 415, asproperly loaded into drive chamber 410, may extend slightly beyonddocking teeth 460. As such, according to embodiments, upon dockingpowered driving device 400, the tip portion of specialized screw 415 mayautomatically create a small impression, or guide hole, in the outercortex of the bone by virtue of its suitably hard and sharp design andits extended position relative to the docking teeth 460. According toalternative embodiments, specialized screw 415 may be initially loadedinto drive chamber 410 in a retracted position and, upon determinationof an appropriate docking location and properly docking the powereddriving device 400, the specialized screw 415 may then be extended.According to this embodiment, specialized screw 415 may be extended viaa trigger control or any other suitable method and, upon extension, maycreate the small impression, or guide hole, in the outer cortex of thebone.

According to embodiments, stop component 465 may be provided forpreventing counter-sinking of the specialized screw. That is, accordingto embodiments, stop component 465 may detect when a crown portion ofthe specialized screw reaches an end of the drive chamber 410 and maycommunicate with the safety trigger component or other appropriatecomponent to automatically shutdown powered driving device 400.According to embodiments, stop component 465 may include a brushapparatus (shown), pressure sensor (not shown), magnetic sensor (notshown), or other suitable device for detecting the crown portion of thespecialized screw. For example, as illustrated, the brush apparatus maybe disposed so as not to come in contact with the screw until a widercrown portion reaches the end of the drive chamber 410. That is, a space470 may be provided between the brush apparatus and the screw such thatthe space 470 prevents contact with the screw until the crown portion,which is wider than the space 470, reaches the end of drive chamber 410and comes in contact with the brush apparatus. According to otherembodiments, the crown portion may be comprised of an alternative typeof metal detectable by a magnetic sensor, for example. Alternatively,stop component 465 may detect that the driver interface of drive shaft425 has reached the end of drive chamber 410. According to embodiments,upon detection that the specialized screw crown portion and/or the driveshaft 425 have reached the end of drive chamber 410, stop component 465may initiate automatic shutdown of powered driving device 400.

As may be appreciated, illustration and description of the variouscomponents and apparatuses associated with powered driving device 400are provided for purposes of explanation and example only. Indeed, anysuitable powered driving device for safely and accurately placing aspecialized screw into a bone may be included within the spirit of thepresent disclosure.

FIG. 5 is an illustration of a second embodiment of a powered drivingdevice as described herein.

According to embodiments, the second embodiment of a powered drivingdevice, e.g., powered driving device 500, may be substantially similarto powered driving device 400. According to some embodiments, FIG. 5provides additional illustrative description for features not visible inFIG. 4.

According to embodiments, powered driving device 500 may comprise anysuitable powered driving device for accurately inserting a specializedscrew into a bone. As described above, powered driving device 500 mayfurther comprise an elongated, cylindrical drive chamber 510. Accordingto embodiments, drive chamber 510 may be adjustable or otherwise alteredfor accommodating various types and sizes of specialized screws, as withdrive chamber 410. According to alternative embodiments, a plurality ofdifferent sized drive chambers 510 may be manufactured corresponding toparticular specialized screw types and size ranges, for example.According to this embodiment, different sized drive chambers 510 may beinterchanged and mechanically coupled to powered driving device 500according to any suitable method.

According to further embodiments, drive chamber 510 may be configuredwith a loading aperture 520. Loading aperture 520 may be provided in anysuitable location on powered driving device 500 such that a specializedscrew, e.g., specialized screw 530, may be loaded into powered drivingdevice 500. That is, loading aperture 520 may be provided on a sideportion of powered driving device 500 (shown), a top portion of powereddriving device 500 (not shown), a bottom portion of powered drivingdevice 500 (not shown), or any other suitable location such thatspecialized screw 530 may be loaded into drive chamber 510 and coupledto drive shaft 540 via drive shaft interface 550.

As described above, powered driving device 500 may be docked onto abone, e.g. medial to a transverse process of a vertebra of interest,upon confirming an appropriate insertion location and trajectory.Further, as described above, an appropriate specialized screw sizehaving specific dimensions may be determined based on a simulatedspecialized screw placement from the docked location of powered drivingdevice 500, e.g., calculated by the image-guidance system utilizing a“look-ahead” feature. Thereafter, according to embodiments, anappropriate specialized screw, e.g., specialized screw 530, may beloaded into drive chamber 510 via loading aperture 520 without undockingand/or reconfirming an appropriate insertion location and trajectory forpowered driving device 500.

As discussed above, upon loading specialized screw 530, microcurrent maybe delivered to specialized screw 530 via any suitable method. As may beappreciated, upon docking powered driving device 500 to bone andpartially inserting specialized screw 530 into the bone, microcurrentmay be delivered to specialized screw 530 and may flow across the bone.According to embodiments, fluctuations in microcurrent may be detectedby the neuro-monitoring apparatus 180, an internal ammeter (not shown),or any other appropriate apparatus or device (not shown).

As discussed above, the powered driving device 500 may be automaticallyand substantially immediately shutdown when microcurrent across the boneregisters below a predetermined threshold, e.g., at or below about 12mA, indicative that specialized screw 530 may imminently traverse orfracture the bone. According to embodiments, during specialized screwplacement, when the microcurrent is recorded within a predeterminedrange, e.g., a range between about 12 and 16 mA for example, an alertmay be generated such that a clinician may be warned that specializedscrew 530 may be approaching a cortical bone layer and/or may have animproper trajectory. As described above, any other appropriate sensor ordevice may be employed to monitor the position of a specialized screw(not shown) and to initiate automatic shutdown of powered driving device500 when such appropriate device senses that specialized screw 530 mayimminently traverse and/or fracture the bone.

As described above, drive shaft 540 may be mechanically or otherwisecoupled to a drive component (not shown). According to embodiments, thedrive component may provide a suitable force in the form of torque, orotherwise, via drive shaft 540 to a specialized screw housed in drivechamber 510. Drive shaft 540 may further include a drive shaft interface550 for engaging a screw interface on the crown portion of specializedscrew 530, for example. According to embodiments, drive shaft interface550 may comprise any common drive design, e.g., octagonal (shown),Robertson (square, not shown), hexed (not shown), Torx (star, notshown), etc., or may include any suitable specialized drive design (notshown) for properly and securely engaging and mating with a suitablescrew interface (not shown). According to some embodiments, drive shaftinterface 550, having octagonal design (shown) or other design (notshown), may further comprise a conical portion for securely engaging andmating with a suitable screw interface, for example suitable screwinterface 380 as described above. As may be appreciated, drive shaftinterface 550 may also include any other suitable portion (not shown)for securely engaging and mating with a suitable screw interface.

According to embodiments, drive shaft interface 550 may be interchangedsuch that the powered driving device 500 may interface with a variety ofscrew interfaces. For example, drive shaft interface 550 may beexchanged via a quick-release coupling, a chuck apparatus, or otherwise.

As described above, the drive component may be mechanically,electrically, or otherwise coupled to a suitable power source by powercoupling apparatus 560. According to alternative embodiments, powercoupling apparatus 560 may be replaced by a battery pack or othersuitable cordless power-delivery apparatus. According to furtherembodiments, a safety trigger component (not shown) may be coupled tothe power switch 570 for facilitating automatic shutdown powered drivingdevice 500. According to alternative embodiments, the safety triggercomponent may comprise an alternative power-off switch. In the case ofelectrical embodiments of the powered driving device 500, the electricalcurrent utilized for powering the driving device may be adequatelyinsulated from an internal ammeter and/or grounded apart fromneuro-monitoring apparatus 180 such that microcurrent across the bonemay be independently monitored and detected.

As described above, powered driving device 500 may also be configuredwith tracking apparatus 580 (partially shown). Tracking apparatus 580may communicate an exact location of powered driving device 500 withinthe image-guidance field at all times.

As described above, powered driving device 500 may further include analert module 575 for providing various monitoring and alarm functionswithin powered driving device 500. According to embodiments, alertmodule 575 may issue alerts regarding proper positioning while powereddriving device 500 is being adjusted over a surgical site. According toother embodiments, the alert module 575 may provide various alertsregarding proper positioning of the specialized screw 530 while it isbeing delivered. According to further embodiments, alert module 575 mayprovide any other suitable alerts to a clinician via any suitable meansduring powered delivery of a screw into bone.

Further, as described above, powered driving device 500 may include atrigger drive 585 for initiating insertion of the specialized screw 530.Trigger drive 585 may also be configured to simultaneously trigger avirtual image guidance display such that the clinician is provided withreal-time virtual feedback regarding the orientation and advancement ofpowered driving device 500 and specialized screw 530. Alternatively,trigger drive 585 may include a trigger guidance control 590 that mayinitiate image guidance upon demand when desired by the clinician.

According to embodiments as described above, powered driving device 500may comprise docking teeth 595 and a stop component (not shown).According to embodiments, docking teeth 595 may be configured to providestabilization support for docking powered driving device 500 on or nearan anatomical landmark or process. Specifically, powered driving device500 may be docked in an appropriate insertion location medial to atransverse process of a vertebra of interest such that, based on aprojected trajectory and exact dimensions of specialized screw 530,specialized screw 530 may be properly inserted into a bone. As describedabove, the stop component may be provided for preventing counter-sinkingof the specialized screw 530.

As may be appreciated, illustration and description of the variouscomponents and apparatuses associated with powered driving device 500are provided for purposes of explanation and example only. Indeed, anysuitable powered driving device for safely and accurately placing ascrew into a bone may be included within the spirit of the presentdisclosure.

FIG. 6 is an illustration of a prospective, partial cross-sectional viewof an embodiment of a powered driving device as described herein.

According to embodiments, the prospective view of an embodiment of apowered driving device, e.g., powered driving device 600, may besubstantially similar to powered driving devices 400 and 500, asdescribed above. According to some embodiments, FIG. 6 providesadditional illustrative description for features not visible in FIGS. 4and 5.

Specifically, an embodiment of a tracking apparatus 610 is illustrated.According to embodiments, tracking apparatus 610 may comprise aplurality of trackers, e.g., trackers 620. The plurality of trackers 620may comprise any suitable number of trackers, e.g. three trackers 620(shown). According to some embodiments, rather than a plurality oftrackers 620, a single tracker 620 may be provided. As described above,trackers 620 may include any suitable tracking device for detectionwithin an image-guidance field, e.g., light-emitting diodes (LEDs),mirror-like balls, electromagnetic coils, global positioning units, etc.The plurality of trackers 620 may be configured in any suitable arraysuch that XYZ coordinates associated with the powered driving device 600may be determined by the image-guidance system. For example, thelocations of LED or mirror-like ball trackers 620 may be detected bystereo camera apparatus 140 and communicated to computing system 160such that a location of the powered driving device 600 may be simulatedin real time within image displays of the patient's anatomy.

According to embodiments, as described above, based on a location andorientation of tracked powered driving device 600 withinthree-dimensional space, the image-guidance system may calculate atrajectory of powered driving device 600 and a predicted or simulatedplacement of an associated specialized screw in real time. That is, atany time, upon docking the powered driving device 600 to bone and/orduring insertion of the associated specialized screw, the image-guidancesystem may provide real-time feedback by continuously calculating avirtual trajectory and a simulated placement of the associatedspecialized screw as it is advanced into the bone.

As described above, powered driving device 600 may further include analert module 630 for providing various monitoring and alarm functions ofpowered driving device 600. According to embodiments, alert module 630may issue alerts regarding proper positioning while powered drivingdevice 600 is being adjusted over a surgical site. According to otherembodiments, the alert module 630 may provide various alerts regardingproper positioning of a specialized screw while it is being delivered.

As may be appreciated, illustration and description of an image-guidancesystem for use with the disclosed powered driving device is provided forpurposes of explanation and example only. Indeed, within the spirit ofthe present disclosure, any image-guidance system either now known ordeveloped in the future may be utilized in combination with thedisclosed powered driving device for safely and accurately placing ascrew into bone.

FIG. 7A is an illustration of a sagittal view of an embodiment of aproperly placed screw in a pedicle as described herein. FIG. 7B is anillustration of an axial view of an embodiment of a properly placedscrew in a pedicle as described herein. FIG. 7C is an illustration of anaxial view of a first improperly placed screw in a pedicle as describedherein. FIG. 7D is an illustration of an axial view of a secondimproperly placed screw in a pedicle as described herein.

FIG. 7A is an illustration of a sagittal view of an embodiment of aproperly placed screw in a pedicle as described herein.

As described above, an image-guidance system may be deployed by placinga stationary tracker on a spinous process near a surgical site, forexample, spinous process 760 or other adjacent spinous process.Thereafter, a powered driving device 710 may be registered within theimage-guidance system. According to embodiments, the powered drivingdevice 710 may be docked via docking teeth 720 in an appropriatelocation for inserting a specialized screw through a pedicle 730 ofvertebra 750. For example, the powered driving device 710 may be dockedon the exterior of the vertebra, e.g., on a lamina medial to atransverse process, e.g., transverse process 785. Thereafter, accordingto embodiments described herein, a specialized screw may be insertedinto the pedicle 730 by powered driving device 710, e.g., specializedscrew 740. For illustrative purposes, pedicle 745 corresponds to apedicle of adjacent vertebra 755.

FIG. 7B is an illustration of an axial view of an embodiment of aproperly placed screw in a pedicle as described herein.

As described above, according to embodiments, the powered driving device710 may be docked via docking teeth 720 in an appropriate location forinserting a specialized screw into a pedicle 730, e.g., medial to atransverse process 785. As illustrated, pedicle 730 corresponds to oneof a pair of narrow bone channels, or roots, of a vertebral arch thatconnect a lamina 775 to a vertebral body 795 of vertebra 750. Pedicle735 refers to the other pedicle of the pair of pedicles of vertebra 750.

As illustrated, the narrow channel of bone corresponding to pedicle 730is provided between a spinal canal 790 that houses the spinal cord and alateral exterior of the vertebra. According to embodiments describedherein, a specialized screw 740 may be inserted through cortical bonelayer 780 into lamina 775, through pedicle 730, and into vertebral body795, where proper placement may be accomplished. As may be appreciated,there is minimal allowance for error in placing specialized screw 740through pedicle 730 because pedicle 730 may only be a few millimeterswider than specialized screw 740.

According to embodiments, target trajectory 725 may be calculated.Target trajectory 725 corresponds to a trajectory that is calculated todeliver specialized screw 740 into a target position, as describedabove. As illustrated, when the specialized screw 740 follows targettrajectory 725, the specialized screw 740 may be properly delivered intoa target position through lamina 775, through pedicle 730, and intovertebral body 795 within a trabecular bone layer 770.

As illustrated by the axial view of vertebra 750, the cortical bonelayer 780 is provided on exterior surfaces of vertebra 750 and adjacentto spinal canal 790. Thus, according to embodiments described herein,when microcurrent monitoring or other sensory device detects that a tipof specialized screw 740 is in contact with cortical bone, this mayindicate that the specialized screw 740 is in danger of breaking intothe spinal canal 790. For example, a microcurrent may register at orbelow about 12 mA when the specialized screw 740 is near or contactingcortical bone. As described above, if the specialized screw 740 contactsthe spinal cord, serious harm to a patient may result, includingparalysis or death.

Also illustrated in the axial view is trabecular bone layer 770, whichrefers to the spongy bone on an interior of the vertebra 750 andsurrounding specialized screw 740 when it is properly placed. Accordingto embodiments described herein, when microcurrent monitoring or othersensory device detects that specialized screw 740 is in contact withtrabecular bone a clinician may verify that the specialized screw 740 isproperly advancing through a pedicle and into a vertebral body. Forexample, a microcurrent may register at or about 20 mA when thespecialized screw 740 is within trabecular bone layer 770.

FIG. 7C is an illustration of an axial view of a first improperly placedscrew in a pedicle as described herein.

As described above, according to embodiments, the powered driving device710 may be docked via docking teeth 720 onto an improper location forinserting a specialized screw into a pedicle 730 of vertebra 750. Thatis, when powered driving device 710 is docked onto improper location,the specialized screw 740 may be directed via improper trajectory 765.According to embodiments described herein, an appropriate insertionlocation may be determined based on an alert indication from powereddriving device 710. However, based on clinician error or otherwise,powered driving device 710 may be docked onto an improper location.

As described above, when specialized screw 740 advances according toimproper trajectory 765, the powered driving device 710 may issue analert or otherwise, as described above. According to furtherembodiments, if specialized screw 740 continues advancement according toimproper trajectory 765, the powered driving device 710 may detect thatthe specialized screw 740 may imminently contact, breach, and/orfracture cortical bone, e.g., medial cortical bone 782. If it isdetermined that specialized screw 740 may imminently breach and/orfracture cortical bone, the powered driving device 710 may beautomatically shutdown, as described herein.

FIG. 7D is an illustration of an axial view of a second improperlyplaced screw in a pedicle as described herein.

As described above, according to embodiments, the powered driving device710 may be docked via docking teeth 720 onto an improper location forinserting a specialized screw into a pedicle 730 of vertebra 750. Thatis, when powered driving device 710 is docked onto an improper location,the specialized screw 740 may be directed via improper trajectory 768.

As described above, when specialized screw 740 advances according toimproper trajectory 768, the powered driving device 710 may issue analert or otherwise, as described above. According to furtherembodiments, if specialized screw 740 continues advancement according toimproper trajectory 768, the powered driving device 710 may detect thatthe specialized screw 740 may imminently contact, breach, and/orfracture cortical bone, e.g., lateral cortical bone 784. If it isdetermined that specialized screw 740 may imminently breach and/orfracture cortical bone, the powered driving device 710 may beautomatically shutdown, as described herein.

FIG. 8 is a flow-diagram illustrating an embodiment of a method forplacing a screw into a bone using a powered driving device.

As should be appreciated, the particular steps and methods describedherein are not exclusive and, as will be understood by those skilled inthe art, the particular ordering of steps as described herein is notintended to limit the method, e.g., steps may be performed in differingorder, additional steps may be performed, and disclosed steps may beexcluded without departing from the spirit of the present methods.

At collect volumetric data operation 802, two-dimensional and/orthree-dimensional volumetric data may be collected from a patient.Embodiments of the present disclosure include collecting volumetric datausing an X-ray device, such as a fluoroscopic device that may obtain aplurality of X-rays while rotating about 190 degrees within the patient.Other embodiments may involve an intra-operative CT scanning device thatmay provide a plurality of image displays. According to embodiments, thevolumetric data may then be loaded into an image-guidance system andconverted into a plurality of three-dimensional images. As may also beappreciated, pre-operative imaging data collected from the patient mayalso be employed within the image-guidance system. For example, theimage-guidance system may include a display having a plurality of viewsfor providing imaging data from various sources to a clinician, e.g.pre- and intra-operative images including images generated via X-ray,CT, MRI, etc. In addition, the image-guidance system may project aposition of a powered driving device and/or a specialized screw ontoeach of the displayed plurality of views.

At employ and verify operation 804, an image-guidance system may beemployed and verified according to any suitable method. According toembodiments, any suitable image-guidance system either now known orlater developed may be utilized for placing a screw into bone with thedisclosed powered driving device. For example, according to embodiments,an image-guidance system may be employed using active infraredtechnologies, e.g. via a stationary LED tracker affixed to a spinousprocess of the patient, or other technologies presently available ordisclosed in the future for mapping the plurality of two- andthree-dimensional images to the three-dimensional space of the patient.For example, as described above, locations of LED or mirror-like ballunits on the stationary tracker may be detected by stereo cameraapparatus 140 and communicated to computing system 160 such that alocation of the spinous process in three dimensional space may be mappedto a corresponding location of the spinous process within the imagedisplays.

As described above, upon generating the image-guidance field,verification of the image-guidance system may be performed. Any suitableverification method may be employed and embodiments may includeutilizing a probe, or other suitable device, to register the infraredfield generated by the image guidance system. According to embodiments,the probe may comprise a tracking apparatus such that the image-guidancesystem may detect an actual location and orientation of the probe withinthree-dimensional space. Further, a virtual location of the probe may becalculated and simulated within the image displays of the patient'sanatomy.

According to embodiments, the image-guidance field may be verified usinga plurality of fiducial markers as reference points within thethree-dimensional space of the patient. Specifically, fiducial markersmay refer to any suitable anatomical landmark or other feature that maybe visually recognized by the clinician within the three-dimensionalspace of the patient's anatomy and within the image displays of thepatient's anatomy. According to embodiments, when the probe is touchedto each of the plurality of fiducial markers, the projection of theprobe's location within the image displays should be reflected on ornear images of each fiducial marker to within an acceptable degree ofdeviance, e.g., 1 millimeter. In the case of an unacceptable degree ofimage deviance, a point-to-point registration may be used to recollectimaging data. Once accuracy of the image-guidance system is established,a probe may be touched to other known anatomical features and landmarksassociated with an area of interest specific to a particular surgicalprocedure, again confirming the accuracy of the image-guidance system.

At registration operation 806, a powered driving device may becalibrated or registered within the image-guidance system. The powereddriving device may be any suitable device having the features describedherein, as described above. Particularly, the powered driving device maybe configured with a tracking apparatus, as described above, such thatit may be registered within the image-guidance field. According toembodiments, upon activation of the tracking apparatus (or uponautomatic activation), a location and orientation of the powered drivingdevice may be detected and reflected on image displays of the patient'sanatomy. According to embodiments, and similar to the verificationmethod described above, the powered driving device may be touched toeach of the plurality of fiducial markers in order to verify that theprojection of the powered driving device's location within the imagedisplays is reflected on or near images of each fiducial marker (e.g.,to within 1 millimeter acceptable deviance).

At docking operation 808, the registered powered driving device may beutilized on a surface of the patient's skin, or on any other suitableanatomical surface, to locate an appropriate docking location. Accordingto embodiments, registered powered driving device may be used toidentify a specific anatomical landmark of interest based on a virtuallocation of the powered driving device on the image displays. Forexample, a particular pedicle of interest may be located. Furtherembodiments include marking on the surface of the patient's skin theparticular location of the pedicle and a corresponding anatomicallocation for placement of the specialized screw. As described above, thepowered driving device may further provide an alert such that aclinician may be directed by the device to an appropriate insertionlocation. That is, a visual and/or audio indication may communicate thatthe powered driving device is positioned over the appropriate insertionlocation. Thereafter, according to embodiments, a small incision may bemade in the patient's skin and the powered driving device may beadvanced through the incision and an appropriate docking location may bedetermined.

According to embodiments, an appropriate docking location may bedetermined by adjusting the powered driving device about a surgicalsite. According to some embodiments, the powered driving device mayprovide an alert when the powered driving is positioned over anappropriate insertion location and when the powered driving device isoriented according to an appropriate trajectory. That is, embodimentsallow for determination of an appropriate location for docking thepowered driving device based on visual anatomical landmarks and/orfeedback from the image-guidance system. Further, embodiments allow fordetermination of the appropriate trajectory for delivering thespecialized screw into a target location based feedback from theimage-guidance system, for example. Specifically, the powered drivingdevice may include a location feedback component that allows a suitablesoftware application, as discussed below, to receive a location of a tipand an orientation of the powered driving device in three-dimensionalspace from a tracking apparatus at all times. According to embodiments,the tracked location and orientation of the powered driving device maybe used to calculate a virtual position and trajectory of the powereddriving device on image displays at all times. According to embodiments,powered driving device may detect and communicate when the virtualtrajectory of the specialized screw matches a target trajectory forproper placement of the specialized screw into a target position. When aclinician confirms that the insertion location and the trajectory of thepowered driving device are appropriate for properly placing thespecialized screw into the target position, the powered driving devicemay be docked onto the bone.

That is, the powered driving device may be docked near a selectedanatomical landmark, such as a transverse process of the spine. Asshould be appreciated, any method or process, whether manual orotherwise, for determining an appropriate insertion location for dockingthe powered driving device is well within the present disclosure.Embodiments of the present methods may include image-guided, visual,and/or tactile placement of the powered driving device onto the selectedanatomical landmark such that accurate docking is achieved. Furtherembodiments include re-verifying imaging accuracy by undocking thedriving device from the selected anatomical landmark and touchingvarious portions of the selected anatomical landmark that may bevisually, tactilely, or otherwise recognized and verified. For example,the driving device may be selectively placed on top of a transverseprocess of interest, on bottom of the transverse process, and then ontothe middle of the transverse process.

Further embodiments may include docking teeth on a tip of the powereddriving device for stabilizing placement and preventing slippage duringdocking of the powered driving device onto the selected anatomicallandmark. As may be appreciated, upon proper docking of the powereddriving device on the bone, a self-drilling tip portion of a specializedscrew may contact and automatically create a small impression, or guidehole, in the outer cortex of the bone. That is, according to someembodiments, upon proper docking of the powered driving device onto thebone, the tip of the specialized screw may be at least partiallydisposed within the hard outer cortex of the bone. According toalternative embodiments, the specialized screw may be initially loadedinto the drive chamber in a retracted position and, upon properlydocking the powered driving device onto the bone the specialized screwmay be extended. According to this embodiment, upon extension of thespecialized screw, the specialized screw may create the smallimpression, or guide hole, in the outer cortex of the bone.

At simulate operation 810, any suitable type of suitable simulation orimaging software may be employed. The suitable software may beconfigured so as to simulate placement of the specialized screw based onexact dimensions of the specialized screw and a virtual trajectory ofthe powered driving device. For example, as discussed above, thesuitable software may relay real-time location feedback, in the form ofa three-dimensional display or otherwise, regarding the location andorientation of the powered driving device, the specialized screw, orboth. As described above, the a calculated or virtual location andorientation of the powered driving device may be reproduced on imagedisplays of the patient's anatomy, i.e., the simulated location of thepowered driving device may be provided within the display images of thebones and anatomical landmarks of the patient's anatomy.

For example, embodiments of the present disclosure may allow theclinician to input a particular make, type, or size of the specializedscrew into the suitable software such that the precise length anddiameter of the screw is accounted for in the display imagery.Alternative embodiments of the present disclosure may enable the powereddriving device to detect the size and type of the specialized screw andto automatically relay that data to the suitable software. As such, asthe clinician makes minor adjustments in the orientation of the powereddriving device, which are automatically communicated to the suitablesoftware, revised trajectories and depth calculations for thespecialized screw may be automatically displayed. The clinician may makeany number of appropriate adjustments while monitoring the display inorder to direct the precise placement of the specialized screw into atarget position (to within 1 millimeter of accuracy, for example).

The suitable software may be further configured to comprise differentmodules or components that may provide different aspects of the visualdisplay and different types of useful and appropriate data for use inaccurately placing a bone screw. As described above, embodiments of thedisclosed methods may employ any suitable computing system for executingthe disclosed suitable software, or any appropriate and useful variationof the disclosed suitable software.

At initiate operation 812, after final verification of the predictedplacement of the specialized screw, the powered driving device may beinitiated. Initiation of the driving device may be made by any suitabletrigger drive. According to embodiments, the trigger drive may beconfigured to prevent accidental initiation and/or shutdown of thepowered driving device. Following initiation of the powered drivingdevice, real-time feedback from the image guidance system may continuesuch that the clinician may view a simulated specialized screw on theimage display as the actual specialized screw is being inserted into thebone. Further, embodiments may also allow for an automatic shutdown ofthe powered driving device if the virtual screw is projected to breachthe bone by the image-guidance system. As such, this embodiment mayallow for automatic shutdown of the driving device even prior to amicrocurrent-monitoring automatic-shutdown feature, as described below,providing an additional layer of protection against potential inaccurateplacement of the screw.

At deliver operation 814, a microcurrent, e.g., in mA, may be passedthrough the specialized screw and into the bone. As described above, themicrocurrent may be automatically initiated upon partial insertion ofthe specialized screw based on a predetermined threshold. According toalternative embodiments, the microcurrent may be initiated when thepowered driving device is appropriately docked onto the bone.Alternatively, microcurrent may be manually initiated based on cliniciandiscretion. As will be recognized by those skilled in the art,microcurrent may be passed into the specialized screw by any suitablemethod, including but not limited to, microcurrent passed along theinterior walls of the driving device and establishing any suitableelectrical connection with a drive shaft coupled to the specializedscrew or to the specialized screw itself. Alternately, microcurrent maybe delivered directly to a crown portion of the specialized screw andthe walls of the driving device may be constructed of any suitablenon-conductive material.

Embodiments of the present systems may utilize fluctuations in themicrocurrent for providing a fail-safe feature and/or an alert feature.For example, as described above, the powered driving device may beautomatically and substantially immediately shutdown when themicrocurrent across the bone registers below a predetermined threshold,e.g., at or below about 12 mA, indicative that specialized screw mayimminently traverse and/or fracture the bone. According to otherembodiments, during specialized screw placement, when the microcurrentregisters within a predetermined range, e.g., a range between about 12and 16 mA for example, an alert may be generated such that a clinicianmay be warned that specialized screw may be approaching the corticallayer and/or may be oriented according to an improper trajectory.

At insertion operation 816, a specialized screw may be placed into thebone of interest. Specifically, the image-guidance data may be fed intothe suitable software to provide real-time feedback while thespecialized screw is being inserted into the bone. In contrast toprevious methods and systems, the clinician may monitor thethree-dimensional image display during screw insertion, which relays avirtual trajectory of the driving device and/or simulated advancement ofthe specialized screw in real-time to the clinician. As such, thepresent methods may provide immediate, precise feedback moment-by-momentduring a surgical procedure. Embodiments of the present methods provideaccurate placement of a specialized screw into a bone of the spine, forexample. Other embodiments of the present systems may include theaccurate placement of any compatible screw into an appropriate bone.

As may be appreciated, description of a method for placing a screw intoa bone using a powered driving device is provided for purposes ofexplanation and example only. Indeed, although the method is describedas a series of steps, each step should not be understood as a necessarystep, as additional and/or alternative steps may be performed within thespirit of the present disclosure. Additionally, described steps may beperformed in any suitable order and the order in which steps weredescribed is not intended to limit the method in any way.

FIG. 9 is a flow-diagram illustrating a first embodiment of a method forautomatically shutting down a powered driving device during screwplacement.

At initiate operation 902, after verification of a predicted placementof the specialized screw using the image-guidance system or otherwise,the powered driving device may be initiated, as described above.Following initiation of the powered driving device, real-time feedbackfrom the image-guidance system may continue such that the clinician mayview a simulated specialized screw on the image display as the actualspecialized screw is being inserted into the bone

At deliver operation 904, a microcurrent, e.g., in mA, may be passedthrough the specialized screw and into the bone. As described above,microcurrent may be automatically initiated upon partial insertion ofthe specialized screw based on a predetermined threshold. According toalternative embodiments, the microcurrent may be initiated when thepowered driving device is appropriately docked onto the bone.Alternatively, microcurrent may be manually initiated based on cliniciandiscretion. As will be recognized by those skilled in the art,microcurrent may be passed into the specialized screw by any suitablemethod.

At monitor operation 906, fluctuations in the microcurrent may bemonitored to provide a fail-safe feature and/or an alert feature. As maybe appreciated, composition of a bone may not be uniform and mayinclude, inter alia, a less resistive trabecular layer and a moreresistive cortical layer. According to embodiments, detectedmicrocurrent may fluctuate based on the resistance of the bonesurrounding the specialized screw. As such, monitoring fluctuations inthe microcurrent provides an indication of whether the specialized screwis properly positioned in the trabecular layer, or improperly positionedin contact with the cortical layer. According to embodiments,microcurrent monitoring may be conducted by an internal ammeter or otherdevice of the powered driving device or may be conducted by aneuro-monitoring apparatus.

At detect operation 908, a fluctuation in the microcurrent may bedetected. That is, as the microcurrent may generally register at roughly20 mA when the specialized screw is within the trabecular layer, afluctuation may be detected when the microcurrent registers below about20 mA.

At determination operation 910, the detected fluctuation in themicrocurrent may be evaluated to determine whether it registers below apredetermined threshold. That is, when the detected fluctuationregisters below about 12 mA, the specialized screw may imminentlytraverse and/or fracture the bone. When the detected fluctuation isbelow about 12 mA, the powered driving device may be automaticallyshutdown at shutdown operation 914. When the detected fluctuation is notbelow about 12 mA, the process may continue to determination operation912.

At determination operation 912, the detected fluctuation in themicrocurrent may be evaluated to determine whether the detectedfluctuation registers within a predetermined range, e.g., a rangebetween about 12 and 16 mA for example. That is, when the detectedfluctuation registers within the predetermined range, the specializedscrew may be oriented according to an improper trajectory. When thedetected fluctuation is between about 12 and 16 mA, an alert may begenerated at alert operation 916. When the detected fluctuation is notbetween about 12 and 16 mA, the process may return to monitor operation906.

At shutdown operation 914, the powered driving device may besubstantially immediately and automatically shutdown upon adetermination that the detected fluctuation registered below thepredetermined threshold, as discussed above. According to embodiments,automatic shutdown may be initiated by a safety trigger component. Thatis, the safety trigger component may be substantially immediately andautomatically initiated upon a determination that the detectedfluctuation registered below the predetermined threshold, i.e., shutdownmay occur substantially instantaneously after determination operation910.

At alert operation 916, an alert may be generated upon a determinationthat the detected fluctuation registered within the predetermined range.That is, an alert may be generated such that a clinician may be warnedthat the specialized screw is oriented according to an impropertrajectory, i.e., the specialized screw may not be properly directedtoward the target position. According to embodiments, the alert may begenerated as an audio alert, a visual alert, or any other suitable alertfor communicating a warning to the clinician.

As may be appreciated, description of a method for automaticallyshutting down a powered driving device during screw placement isprovided for purposes of explanation and example only. Indeed, althoughthe method is described as a series of steps, each step should not beunderstood as a necessary step, as additional and/or alternative stepsmay be performed within the spirit of the present disclosure.Additionally, described steps may be performed in any suitable order andthe order in which steps were described is not intended to limit themethod in any way.

FIG. 10 is a flow-diagram illustrating a second embodiment of a methodfor automatically shutting down a powered driving device during screwplacement.

At register operation 1002, a powered driving device may be calibratedwithin an image-guidance field. For example, according to embodiments,the powered driving device may be fitted with light-emitting diodes,global positioning units, magnetic coils, etc., and data regarding theposition of the powered driving device may be collected by a stereocamera apparatus, a GPS system, or otherwise. That is, as the detectedposition of the powered driving device changes within thethree-dimensional space of the patient's anatomy, its virtual positionon image displays may be simultaneously updated in real time. Further,the exact dimensions of the powered driving device may be loaded intothe image-guidance system such that a corresponding virtual powereddriving device may be simulated on the display images. According toembodiments, the simulated position and dimensions of the powereddriving device may be verified by touching the device to variousfiducial markers and/or other known anatomical landmarks and confirmingthat the simulated position of the powered driving device is within anacceptable degree of deviance, e.g., 1 mm, of the anatomical landmarkreflected on each image.

At detect operation 1004, a virtual position of the specialized screwhoused in the powered driving device may be determined. That is,according to embodiments, the exact dimensions of the specialized screwmay be loaded into the image-guidance system. Thus, as theimage-guidance system has knowledge of the registered powered drivingdevice housing the specialized screw, the system may also automaticallysimulate and project the dimensions of the specialized screw onto eachimage. Further still, the image-guidance system may identify anorientation of the powered driving device in three-dimensional space,such that a predicted trajectory for the specialized screw may bedetermined and simulated on the images. Further, upon determining thepredicted trajectory, and with knowledge of the exact dimensions of thespecialized screw, the image-guidance system may simulate a predictedplacement of the specialized screw on the display images.

At initiate operation 1006, after verification of a predicted placementof the specialized screw using the image-guidance system or otherwise,the powered driving device may be initiated, as described above.

At monitor operation 1008, the virtual position of the specialized screwmay be monitored in real time. That is, the image-guidance system maycontinually recalculate and update a virtual position of the specializedscrew based on the trajectory of the powered driving device and theexact dimensions of the specialized screw. Additionally oralternatively, according to embodiments, the image-guidance system maybe in communication with the powered driving device such that theimage-guidance system may be aware of each revolution of the specializedscrew as it is being inserted into the bone. That is, as threaddimensions of the specialized screw may be known to the image-guidancesystem, the system may calculate a depth of the specialized screwassociated with each revolution of the specialized screw. According toembodiments, the image-guidance system may then simulate the virtualposition of the specialized screw based on a trajectory, length, anddepth of the specialized screw in real time for the clinician.

At detect operation 1010, a change in a virtual position of thespecialized screw may be detected. Based on the trajectory, length, anddepth of the specialized screw, the image-guidance system may determinewhether the change in virtual position indicates that the specializedscrew is misaligned or otherwise improperly placed. For example, theimage-guidance system may compare the virtual position of thespecialized screw with a target position communicated by the clinicianor otherwise to the image-guidance system.

At determination operation 1012, the detected change in virtual positionmay be evaluated to determine whether the specialized screw mayimminently traverse and/or fracture the bone. That is, by simulating apredicted position of the specialized screw based on the trajectory andlength of the specialized screw, for example, the image-guidance systemmay determine that the specialized screw may imminently breach thecortical bone layer. If so, the powered driving device may beautomatically shutdown at shutdown operation 1016. If the detectedchange in virtual position indicates that the specialized screw shouldnot imminently traverse the bone, the process may continue todetermination operation 1014.

At determination operation 1014, the detected change in virtual positionmay be evaluated to determine whether a virtual trajectory of thespecialized screw may be improper. For example, the image-guidancesystem may compare a virtual trajectory of the specialized screw with atarget trajectory calculated by the image-guidance system for deliveringthe specialized screw into the target position. If the virtualtrajectory of the specialized screw is improper, i.e., that the virtualtrajectory does not match the target trajectory and may not deliver thespecialized screw into the target position, an alert may be generated atalert operation 1018. If the detected change in virtual positionindicates that the virtual trajectory of the specialized screw is notimproper, the process may return to monitor operation 1008.

At shutdown operation 1016, the powered driving device may beautomatically shutdown upon a determination that the detected change invirtual position may imminently traverse the bone. According toembodiments, automatic shutdown may be initiated by a safety triggercomponent. That is, the safety trigger component may be automaticallyinitiated upon a determination that the detected change in virtualposition may imminently traverse the bone, i.e., shutdown may occursubstantially instantaneously after determination operation 1012.

At alert operation 1018, an alert may be generated upon a determinationthat the virtual trajectory of the specialized screw is improper. Thatis, an alert may be generated such that a clinician may be warned thatthe virtual trajectory does not match the target trajectory and may notdeliver the specialized screw into the target position. According toembodiments, the alert may be generated as an audio alert, a visualalert, or any other suitable alert for communicating a warning to theclinician.

As may be appreciated, description of a method for automaticallyshutting down a powered driving device during screw placement isprovided for purposes of explanation and example only. Indeed, althoughthe method is described as a series of steps, each step should not beunderstood as a necessary step, as additional and/or alternative stepsmay be performed within the spirit of the present disclosure.Additionally, described steps may be performed in any suitable order andthe order in which steps were described is not intended to limit themethod in any way.

FIG. 11 is a flow-diagram illustrating a third embodiment of a methodfor automatically shutting down a powered driving device during screwplacement.

At initiate operation 1102, after verification of a projected placementof the specialized screw using the image-guidance system or otherwise,the powered driving device may be initiated, as described above.

At monitor operation 1104, a position of the specialized screw may bemonitored by sensors during insertion of the specialized screw. Forexample, according to embodiments, suitable sensors may be employed todetect a bone density around the specialized screw. As a bone density ofthe cortical layer may be greater than a bone density of the trabecularlayer, bone density may be used to indicate that a specialized screw isapproaching the cortical layer and is in danger of traversing and/orfracturing the bone. Alternatively, other suitable sensors may beemployed to detect a proximity of the specialized screw to the corticallayer via any other suitable means. For example, sonic devices, radardevices, pressure-sensitive devices, heat-sensitive devices, etc., maybe employed to detect bone density and/or a proximity to the corticallayer.

At detect operation 1106, a change in position of the specialized screwmay be detected. That is, based on data from the suitable sensors, itmay be determined by an associated computing system and/or the powereddriving device that the specialized screw is advancing into the bone.Further, the sensors may detect a change in bone density near thespecialized screw.

At determination operation 1108, the detected change in position may beevaluated to determine whether the specialized screw may imminentlytraverse and/or fracture the bone, i.e., the specialized screw is in animproper position. That is, based on data from the suitable sensors, itmay be determined by the associated computing system and/or the powereddriving device that the specialized screw is in contact with or mayimminently traverse the cortical layer. If so, the powered drivingdevice may be automatically shutdown at shutdown operation 1112. If thedetected change in position indicates that the specialized screw may notimminently traverse the cortical layer, the process may continue todetermination operation 1010.

At determination operation 1010, the detected change in position mayindicate that the specialized screw has an improper trajectory. If thetrajectory of the specialized screw is improper, i.e., the predictedtrajectory does not match the target trajectory and may not deliver thespecialized screw into the target position, an alert may be generated atalert operation 1114. If the detected change in position does notindicate an improper trajectory of the specialized screw, the processmay return to monitor operation 1104.

At shutdown operation 1112, the powered driving device may beautomatically and substantially immediately shutdown upon adetermination that the detected change in position may imminentlytraverse the bone. According to embodiments, automatic shutdown may beinitiated by a safety trigger component. That is, the safety triggercomponent may be automatically initiated upon a determination that thedetected change in position may imminently traverse the bone, i.e.,shutdown may occur substantially instantaneously after determinationoperation 1108.

At alert operation 1114, an alert may be generated upon a determinationthat the trajectory of the specialized screw is improper. That is, analert may be generated such that a clinician may be warned thatspecialized screw may not be delivered into the target position based onthe improper trajectory. According to embodiments, the alert may begenerated as an audio alert, a visual alert, or any other suitable alertfor communicating a warning to the clinician.

As may be appreciated, description of a method for automaticallyshutting down a powered driving device during screw placement isprovided for purposes of explanation and example only. Indeed, althoughthe method is described as a series of steps, each step should not beunderstood as a necessary step, as additional and/or alternative stepsmay be performed within the spirit of the present disclosure.Additionally, described steps may be performed in any suitable order andthe order in which steps were described is not intended to limit themethod in any way.

Unless otherwise indicated, all numbers expressing measurements,dimensions, and so forth used in the specification and claims are to beunderstood as being modified in all instances by the term “about.”Accordingly, unless indicated to the contrary, the numerical parametersset forth in the following specification and attached claims areapproximations that may vary depending upon the desired propertiessought to be obtained by the present disclosure. Further, unlessotherwise stated, the term “about” shall expressly include “exactly,”consistent with the discussions regarding ranges and numerical data.Concentrations, amounts, and other numerical data may be expressed orpresented herein in a range format. It is to be understood that such arange format is used merely for convenience and brevity and thus shouldbe interpreted flexibly to include not only the numerical valuesexplicitly recited as the limits of the range, but also to include allthe individual numerical values or sub-ranges encompassed within thatrange as if each numerical value and sub-range is explicitly recited. Asan illustration, a numerical range of “about 4 percent to about 7percent” should be interpreted to include not only the explicitlyrecited values of about 4 percent to about 7 percent, but also includeindividual values and sub-ranges within the indicated range. Thus,included in this numerical range are individual values such as 4.5, 5.25and 6 and sub-ranges such as from 4-5, from 5-7, and from 5.5-6.5, etc.This same principle applies to ranges reciting only one numerical value.Furthermore, such an interpretation should apply regardless of thebreadth of the range or the characteristics being described.

It will be clear that the systems and methods described herein are welladapted to attain the ends and advantages mentioned as well as thoseinherent therein. Those skilled in the art will recognize that themethods and systems within this specification may be implemented in manymanners and as such is not to be limited by the foregoing exemplifiedembodiments and examples. In other words, functional elements beingperformed by a single or multiple components, in various combinations ofhardware and software, and individual functions can be distributed amongsoftware applications at either the client or server level. In thisregard, any number of the features of the different embodimentsdescribed herein may be combined into one single embodiment andalternate embodiments having fewer than or more than all of the featuresherein described are possible.

While various embodiments have been described for purposes of thisdisclosure, various changes and modifications may be made which are wellwithin the scope of the present embodiments. For example, theimage-guided placement of any type of screw into any type of bone fallswithin the scope of the present disclosure. Further, the image-guidedplacement of screws into the bones of human or non-human vertebrates iswell within the scope of the present disclosure. Numerous other changesmay be made which will readily suggest themselves to those skilled inthe art and which are encompassed in the spirit of the disclosure.

1. A powered driving device for minimal-step placement of a screw into abone, the powered driving device comprising: a drive componentconfigured for delivering torque to a drive shaft, wherein the drivecomponent is powered by a first electrical current; the drive shaftcommunicatively coupled to the drive component, wherein the drive shaftrotates axially when torque is delivered by the drive component; a drivechamber that encases the drive component and the drive shaft, the drivechamber for housing a screw, wherein the screw couples to the driveshaft when housed in the drive chamber; the screw housed in the drivechamber, wherein the screw is configured to be advanced and insertedinto the bone by the axial rotation of the drive shaft, the screwcomprising: a self-drilling tip, wherein the self-drilling tip isconfigured to form an impression in an outer cortical region of the bonein the absence of a pre-drilled guide hole; a flute, wherein the fluteis configured to facilitate advancement of the screw into the bonewithout fracturing the bone in the absence of pre-tapping; and a crownportion at an end of the screw opposite the self-drilling tip; a voltagegenerator for delivering a second electrical current to the screw whenthe screw is at least partially inserted into the bone; a monitoringcomponent for detecting a position of the screw, wherein the monitoringcomponent detects the position of the screw at least in part bymeasuring the second electrical current to determine a resistance of thebone surrounding the screw; an alert component for issuing an alert whenthe monitoring component detects that the screw has an impropertrajectory; a safety trigger for automatically shutting down the powereddriving device when the monitoring component detects the screw is in animproper position; and a stop component for automatically shutting downthe powered driving device before the crown of the screw counter-sinksinto the bone while the monitoring component detects the screw has aproper trajectory and a proper position, wherein the stop componentdetects one of: a) a portion of the screw reaching an end of the drivechamber, or b) a portion of the drive shaft reaching an end of the drivechamber.
 2. The powered driving device of claim 1, wherein themonitoring component further comprises: one or more sensors fordetecting the position of the screw as the screw is delivered into bone.3. The powered driving device of claim 1, wherein the bone is avertebral bone.
 4. The powered driving device of claim 1, wherein themonitoring component further comprises: a meter for monitoring thesecond electrical current flowing through the screw and into the bone,wherein the second electrical current registers below a predeterminedthreshold when the screw is in an improper position, and wherein thesecond electrical current registers within a predetermined range whenthe screw has an improper trajectory.
 5. The powered driving device ofclaim 1, wherein the monitoring component further comprises: one or moresensors for detecting the position of the screw.
 6. The powered drivingdevice of claim 1, wherein the monitoring component further comprises:an image-guidance tracker affixed to the powered driving device; and animage-guidance system for calculating a predicted position of the screwbased on data from the image-guidance tracker.
 7. A powered drivingdevice for minimal-step placement of a screw into a bone, the powereddriving device comprising: a drive component configured for deliveringtorque to a drive shaft, wherein the drive component is powered by afirst electrical current; the drive shaft communicatively coupled to thedrive component, wherein the drive shaft rotates axially when torque isdelivered by the drive component; a drive chamber that encases the drivecomponent and the drive shaft, the drive chamber for housing a screw,wherein the screw couples to the drive shaft when housed in the drivechamber; the screw housed in the drive chamber, wherein the screw isconfigured to be advanced and inserted into the bone by the axialrotation of the drive shaft, the screw comprising: a self-drilling tip,wherein the self-drilling tip is configured to form an impression in anouter cortical region of the bone in the absence of a pre-drilled guidehole; a flute, wherein the flute is configured to facilitate advancementof the screw into the bone without fracturing the bone in the absence ofpre-tapping; and a crown portion at an end of the screw opposite theself-drilling tip; a voltage generator for delivering a secondelectrical current to the screw when the screw is at least partiallyinserted into the bone; a meter for measuring the second electricalcurrent flowing through the screw and into the bone; a monitoringcomponent for detecting a position of the screw, wherein the monitoringcomponent is communicatively coupled to the meter, wherein themonitoring component detects the position of the screw based at least inpart on estimating a resistance of the bone surrounding the screw; asafety trigger for automatically shutting down the powered drivingdevice when the monitoring component detects the screw is in an improperposition; and a stop component for automatically shutting down thepowered driving device before the crown of the screw counter-sinks intothe bone while the monitoring component detects the screw has a properposition, wherein the stop component detects one of: a) a portion of thescrew reaching an end of the drive chamber, or b) a portion of the driveshaft reaching an end of the drive chamber.
 8. The powered drivingdevice of claim 7, wherein the monitoring component further comprises:one or more sensors for detecting the position of the screw as the screwis delivered into bone.
 9. The powered driving device of claim 7,further comprising an alert component for issuing an alert when themonitoring component detects that the screw has an improper trajectory.10. The powered driving device of claim 7, wherein the second electricalcurrent registers below a predetermined threshold when the screw is inan improper position, and wherein the second electrical currentregisters within a predetermined range when the screw has an impropertrajectory.
 11. The powered driving device of claim 7, wherein themonitoring component further comprises: one or more sensors fordetecting the position of the screw.
 12. The powered driving device ofclaim 7, wherein the monitoring component further comprises: animage-guidance tracker affixed to the powered driving device; and animage-guidance system for calculating a predicted position of the screwbased on data from the image-guidance tracker.
 13. A powered drivingdevice for minimal-step placement of a screw into a bone, the powereddriving device comprising: a drive component configured for deliveringtorque to a drive shaft, wherein the drive component is powered by afirst electrical current; the drive shaft communicatively coupled to thedrive component, wherein the drive shaft rotates axially when torque isdelivered by the drive component; a drive chamber that encases the drivecomponent and the drive shaft, the drive chamber for housing a screw,wherein the screw couples to the drive shaft when housed in the drivechamber; the screw housed in the drive chamber, wherein the screw isconfigured to be advanced and inserted into the bone by the axialrotation of the drive shaft, the screw comprising: a self-drilling tip,wherein the self-drilling tip is configured to form an impression in anouter cortical region of the bone in the absence of a pre-drilled guidehole; a flute, wherein the flute is configured to facilitate advancementof the screw into the bone without fracturing the bone in the absence ofpre-tapping; and a crown portion at an end of the screw opposite theself-drilling tip; a voltage generator for delivering a secondelectrical current to the screw when the screw is at least partiallyinserted into the bone; a meter for measuring the second electricalcurrent flowing through the screw and into the bone; a monitoringcomponent for detecting a position of the screw, wherein the monitoringcomponent is communicatively coupled to the meter, wherein themonitoring component detects the position of the screw based at least inpart on estimating a resistance of the bone surrounding the screw; analert component for issuing an alert when the monitoring componentdetects that the screw has an improper trajectory; and a stop componentfor automatically shutting down the powered driving device before thecrown of the screw counter-sinks into the bone while the monitoringcomponent detects the screw has a proper trajectory, wherein the stopcomponent detects one of: a) a portion of the screw reaching an end ofthe drive chamber, or b) a portion of the drive shaft reaching an end ofthe drive chamber.
 14. The powered driving device of claim 13, furthercomprising a safety trigger for automatically shutting down the powereddriving device when the monitoring component detects the screw is in animproper position.
 15. The powered driving device of claim 13, whereinthe second electrical current registers below a predetermined thresholdwhen the screw is in an improper position, and wherein the secondelectrical current registers within a predetermined range when the screwhas an improper trajectory.
 16. The powered driving device of claim 13,wherein the monitoring component further comprises: an image-guidancetracker affixed to the powered driving device; and an image-guidancesystem for calculating a predicted position of the screw based on datafrom the image-guidance tracker.